When the cold sets in and you’re ready to turn on your furnace, it’s important to remember the risk of carbon monoxide poisoning. Gas appliances like furnaces can introduce this deadly gas into your home if they aren’t properly maintained. All it takes is a small crack in the wrong place for your furnace to put everyone in your home at risk.

There is no risk of carbon monoxide poisoning from a furnace in good condition. Don’t ignore your furnace, even if it seems to be working properly. A crack in the exhaust or heat exchanger may not affect performance. It can keep pumping odorless gas into the house, though. Here’s what you should know about CO poisoning and why furnace repairs and maintenance are so important.

Understanding Carbon Monoxide

Carbon monoxide (CO) is a byproduct created when a fuel like natural gas, wood, or kerosene is burned. With your furnace, the carbon monoxide is typically contained within the walls of the heat exchanger. When the furnace is operating properly, the CO is directed through the flue pipe and vented out of the home. If your furnace develops a crack, carbon monoxide can leak out into the home.

It takes less than 1% of your indoor air becoming replaced with carbon monoxide to suffer effects. Within 45 minutes, you may experience nausea and a headache, but unconsciousness can occur within 1 hour. Just two hours in this environment can be lethal. A large amount of CO can overcome you in just a few minutes with no warning at all.

When someone becomes unconscious near the source of the carbon monoxide, it often results in death. Every year, CO poisoning kills about 400 people in the United States while another 20,000 are treated in a hospital.

Improper Maintenance Is the Top Cause

It’s essential to have your furnace inspected and maintained annually. The top cause of carbon monoxide poisoning is a heating system that is poorly maintained. Boilers and furnaces are usually to blame, but wood pellet stoves and wood fireplaces can also create CO. If your furnace is not working correctly or a vent gets blocked, carbon monoxide can leak into your home.

Of these problems, a cracked heat exchanger is the most common. Your furnace heat exchanger is made out of metal. It expands and contracts every time the furnace cools down and heats up again. This can cause the walls of the exchanger to crack under the stress and allow gas to leak into the home. When the furnace is not maintained, it’s possible to develop a crack in the exchanger. This can happen when the unit is just 10-14 years old.

Older Furnaces Are Riskier

Carbon monoxide poisoning is more likely to happen if you have an older furnace. Even regular wear and tear can lead to potentially fatal damage to your furnace. If your furnace is not maintained, the risk is higher.

Regular maintenance and furnace repairs become more important as your furnace ages and parts begin to wear out. Consider replacing your furnace once it approaches 15 years old.

Carbon Monoxide Detectors: First Line of Defense

CO is tasteless, odorless, and colorless. A carbon monoxide detector is the only way to detect the gas. Placing CO detectors around your home can protect your entire family. These devices, like smoke alarms, emit a loud noise when CO levels reach a certain threshold.

For the best protection, add a CO detector near your furnace and another detector on every floor. An alarm should be audible from every bedroom. If a detector goes off, the entire home should be evacuated right away. You should test your CO detectors at the same time as your smoke alarms to make sure they’re working properly.

The Importance of Furnace Repairs and Maintenance

There is a downside to CO detectors. They only detect levels of carbon monoxide that are already quite high. You may still be exposed to smaller but potentially life-threatening levels of carbon monoxide.

The best way to ensure your family is safe is scheduling an annual furnace tune-up. Furnace repairs can prevent fatal damage that may release carbon monoxide into your home. A qualified HVAC technician can also detect minor damage before it worsens and leads to a gas leak.

Proper furnace maintenance also includes changing your air filters regularly. Improper air flow to the furnace is a common cause of CO leaks. Your air filter should be changed monthly or more often if you have pets.

The older your furnace, the more important maintenance and repairs become. On average, a furnace can last for 15-20 years with regular maintenance. As your furnace nears this age, consider replacing it before it suffers potentially critical damage.